Ao, the Dawn Sky + Mortuary + Gigantoplasm

Ao, the Dawn Sky

Mortuary

Gigantoplasm

How it works

1. Cast Gigantoplasm by paying its mana cost. Choose to have it enter the battlefield as a copy of Ao.
2. Put Gigantoplasm into your graveyard due to the legend rule.
3. When Gigantoplasm dies, it and Mortuary trigger.
4. Resolve the Mortuary trigger, putting Gigantoplasm from your graveyard onto the top of your library.
5. Resolve the Gigantoplasm trigger, causing you to look at the top seven cards of your library and put Gigantoplasm onto the battlefield as a copy of Ao.
6. Repeat from step 2.